Cellular composition and method of making the same



Nov. 28, 1933. H. M. SPENCER 1,936,887

CELLULAR COMPOSITION AND METHOD OF MAKING THE SAME Filed June 13, 1931 V IN VEN TOR B Y ......a

z's/l TTORNE Y Fig. 1 is a perspective View of a panel of com-' form in which 'it maybe I Patented Nov. 28, 1933 l I v V v j I UNITED/STATES PATENT ."j I oELLULAR-ooMPosI'rioN AND METHOD CF n r MAKIN GTHE SAME I iifigh 'Spencer, ,Lockpr1:,gl\; Y., assignor' to "The UpsonCpmpany, Lockport, N. Y., ,a cor- I II I I poration of New.oik ""i j, 1 m i i 1 ,WJ -;-1. a; g, Applioationlunerm; 1931.' Serial Nor.544,166

.Y T The present 'ih'vention relates to an intumesuor is thenheated, and under the action of'heat cent composition, and has'for its object the prothe 'mixture will intumesce or swellintoahard vision of arelatively inexpensive, light, service cellular body having numerous SmalI 'p'Ores or I able, and satisfactory composition capable'of' a openings therein somewhat similar to the'cells *5 variety of uses. Another object of the invenof a l oaf of breadr II 1 1 7 tion is the provision of a simpleand satisfactory As an exampleof propo jtions which have been method for making a composition of this charfound to be satisfactory, "tenpeunds of the dry I cter. I I I sulphite liquor pitch may- 'be "dissolvedf-in' five To these and other ends the'invention resides pounds of hot Water, and the resulting fifteen so I 16 in certain improvements and combinations of poundsofsulphite liquor'solution may be'mixed' parts, all as will be hereinafter more fully dewith sixtypounds of limestone-ground to 'a finescribed, the 'novel features being pointed out in 'ness so that over ninety-five .percentthereof the claims at the end of the specification. passes through atwo h undred mesh screen. The

.mixture is then "plaq q m a 'suitable'mold or ated so as'tocause 70 position made in accordance with the present in II intumescence. Satisfactory 'esults are obtained vention, and I I byf'heating to a temperatureof about 340 -to Fig. 2 is a cross section therethrough. 360 'F for example, which heating may con- Similar reference numerals throughout the, veniently'and satisfactorily be accomplished) by In the drawing:

'20 several views indicate the. same parts. placing the material between steam heated 75 I This application is partly a continuation of platens or in a steam heated mold. The mixture my application, Serial No.'352,852, filed April 5, mustnotbeheatedtoora-pidly or the intumescence 1929, for Molded compositions, which has now will beso violent that the mixture'will be blown become Patent No. 1,821,120, granted September out of the mold. On the other hand, if'heated 1, 1931. The present application is filed as a retoo slowly, itwill simply dry out slowlytvithout sult of a requirementifor division by the Patent intumescing to form a cellular product.

Office in the application'which has resulted in the Heating should be continued until all orpracabove mentioned patent. I 'tically all of the moisture is driven from the In the production of wood pulp by the sulphite product. Ordinarily, heating for about ten orf V process, there is produced as a by-product, a sofifteen minutes; at the above temperature pro- 3 called sulphite liquor, which is obtained through duces satisfactory results, whenthe product is the cooking of the wood withan-aqueous solution of approximately the proportions above stated of the acid sulphites of lime and/or magnesium, and is in the form of a panel about inch thick. I I I for example. Thissulphite liquor is available in When the material is in the formof thicker panels,

' great quantities at relatively low cost, because the time of heating may-be somewhat'increased, 9 of the fact that'it' is a by-product of the wood and when the proportions of the ingredients or pulp industries and is usually wasted; A com- 'the temperature'to whichthe material is heated mercial' use for this sulphite liquor has long been are varied, the timeof heating may likewise be I sought." I I 9 more or less than that above stated, as deter-, I 40 The sulphite liquor, originally of an acid charmined by the judgment and skill of the person 95 acter, may be rendered neutral or nearly neutral controlling the process. I g I I bysuitable reagents and may be concentrated The above example of proportions is not'to'be by evaporation, such concentration being preftakenin alimiting sense, buti s given merely as erably, thoughnot necessarily, carried to the an example of conditions Whichwill produce point where a suf ficient amount of water has satisfactory results. It is possible to usIe "li inebeen expelled to produce a substantially dry powstone which is ground either coarser orf finer than der. This powder, "resulting from the concentrathatabove specified, and other materiahsucnias I tion of the sulphite liquor, may be'conveniently ground or pulverized sandstone, shalegslagfor termed sulphite liquor pitch; I 4 various other inorganic materials may'beh'sed' as According to the" present invention, suitable fillersf In general, the finer'thefiller is ground, 105

quantities of dissolved sulphite liquor pitch or the greater is the quantity ofsulphite-liquor of sulphite liquor concentrated to a suitable point solution which is needed, ancl-ithe coarser the short of dryness, are added to a finely divided infiller materialgthe less the quantity ofsulphite I organic filler, such for e'xamplejas ground lime liquor solution. The use of "too 'f coar e sinner stone. The'mixture of filler and sulphite liqis not advantageous, however, beaus'e" the no porosity of the product is less uniform than if a finer material is used. c

-The strength or concentration of the sulphite liquor solution may also be varied, as desired,.al-

platens and to assist in pulling it through the though the portions above specified give satisfactory results in general. If the solution of sul' phite' liquor is too thin, the pores formedin the product during the intumescing operation are too coarse, and the walls surrounding the pores are not sufficiently stiff to prevent collapse of the pores'before the walls harden. Furthermore, if too thin 93 solution is used, the boiling of the 'intumescin'g is not adequate, the pores are too small anoltoo few,'the entire product is crumbly and unsuitable, and the cost thereof is increased because of the cost of the additional sulphite liquor employed. a

i It is difiicult to set absolute limits for the proportions andconcentration of'the materials, since the exactcharacter of the final product desired may be varied. The exact proportionsto be used under any given circumstances are practical matters rather than theoretical, and the general principles involved have been sufiiciently set forth aboveso that those skilled in the art can produce satisfactory results by following these prin ciples and by using their skill and judgment.

During the heating and intumescing of the product it is preferably confined in a mold or;

otherwise togive it the desired shape or form, and to prevent unlimited expansion. If not cone fined when intumesced, the pores will become so controlled to some extent by varyingthe ratio the cubic capacity of the mold. Obviously if the.

of mixture introduced into the mold relative. to

only to a relatively slight extent, so that the pores will be smaller and the material'will be relatively dense. On the other hand, if a less quantity the intended thickness of the final product. 1 The I of material is introduced into the mold; when it intumesces it can expand to a greater degree to fill the mold, so that the pores will be larger and the material will be less dense. 1

The molds in which the material is intumesced may be of any suitable form, such as 'molds' mixture of filler and sulphite liquor may be in-'- troduced betweenthe platens at one end. or edge and moved continuously therethrough toward the opposite end or edges, emerging as afinished intumescedslab or sheet, which may be further heat treated toharden it'if desired, in case it is not sufiiciently hard when {it emerges from the platens after the. intumescing operation is .fin-

ished.. WhenLusing a'mold' of this form, .slabs or sheets of material of the desiredthickness can be produced substantially continuously, the mixture being fed substantially continuoush to one end or edge of the platens and the intumesced product being withdrawn substantially continuously from the other end or edge.

To prevent the product from sticking to the platens, liners are preferably used on opposite sides of the product and preferably move througlr th'e'platens with the product. These liners may be in the form of paper orcardboard which may remain permanently attached to the opposite "faces of the product, or they may be of any suitable sheet-material, including paper or card-1 boardsubsequently stripped or removed from the product. For example, if the liners are to be stripped they maybe of waxed or greased paper which will not stick "tenaciouslyto the product, or of. greased sheets of metal which] ;will move through the platens with the product,

2, in which the main body of the material is designated by the numeral 10, and some of the pores are'indicated bythenumeral 11.

An intumescent composition employing sul- I phite'liquor according to the present invention,

has advantages over intumescent compositions in which sodium silicate isused, in that the sulphite liquor composition is in-general somewhat lighter than the sodium silicate composition for a given 'thicknessand strength, and the'sulphite liquor is of materially lower cost than-the sodium sili- I cate necessaryto producev the same quantity of product. I V V I claim:

1. Themethod or" making a cellularcomposition which comprises forming a mixture of relatively'finely divided inorganicmateria1 and sulphite liquor 'solution,.a nd heating said mixture to cause it to intumesce to form a cellular prod- V uct.

2. The method ofmakinga oellularcomposb" tion which comprises evaporating sulphite liquor substantially to dryness to form sulphite liquor pitch, adding water to such pitch toform a sul- 3. The method of making a cellular composition which comprises forming a mixture of relatively finely divided inorganic materialand sulphite liquorsolution, and heating said mixture to approximately 350? F. tocause it toin'tumesce.

' 5. As a new article of manufacture, a hard cellular composition consisting principally of a mixture of relatively f nely divided inorganic material and a sulphite liquor product.

6.'As anew article of manufacturea hard cellularcomposition comprisingfa mixture of. relatively finelydivided inorganic'material and sulphite liquor pitch.

'7. A composition comprising relativelyfinely divided inorganic materialand'a sulphite liquor product, said composition beingiformediinto a relatively hard porousmass having a multitude of cells interspersedtherein. c v 7 7 'HUQI IfMJ-SPENCER, 

